Convince a sceptic (me) on polyculture

As the title says, I want to set up a bed to see if pollyculture would be better than the single species beds I generally use, I don't think it would be I think it will mean reduced yield, increased competition and much more work trying to weed and harvest, plus increased losses as interventions become harder. I want to plant one bed in a mix of plants and use single species beds in the same situation as the controls.

So how would you set up such an experiment?
Where would you site it?
What would you plant in it?
How much space would you leave between plants?
How much intervention/products would you use?

Siting choices;

Full sun tilled soil,
Part sun (morning) tilled soil
Part sun (evening) tilled soil
Part sun (Morning) untilled unmown "pasture"
Part sun (Evening) untilled unmown "pasture"
Full shade untilled

Each bit can be close to the main vegetable garden or away from it.

Mulch if required can be woodchips which are partially decomposed, cardboard and/or straw.

Sizing will be 1m wide by whatever long. as the main beds are 1m wide by 28m long

The main problem plants are Cabbage family, carrots and then turnips/radishes. all of them have nasty pests that totally destroy the plants. I grow way to much to hand pick pests or even look at each plant every day. Beans/squash etc don't have any particular pests here. The main non specific pests are slugs, and voles The climate is cool, damp and windy. soil is around 8-8.5pH shallow and directly above chalk. Watering is uncommon, generally only once or twice a year. The main weeds are fat hen, creeping buttercup, couch grass, dandelion, creeping thistle, knotweeds, black nightshade and chickweed. The garden area is surrounded on 1 side by a conventionally managed winter barley field, on the next side by an unmanaged mixed species hedgerow, the third side is 5m of wild grass/flowers then a road and a conventional maize field, and the last side is my orchard, mixed fruit trees, fruit bushes, and mixed understory mainly grass but also nettles, strawberries, wood avons, lesser celandine etc etc.

Annuals/biannuals I grow include. Potatoes, carrots, parsnips, peas, beans, Summer and winter squash (the latter NOT in the beds) lettuce, spinach, onions, leeks, beetroot, sill, parsley, coriander, marigolds, snapdragons, sunflowers, poppies. Perennials in the same area include horseradish, chives, strawberries, asparagus, fennel, garlic, dahlias.


The metrics to measure success would be yield per m2, time taken to weed/manage the bed including thinning and any tying up that is required and time taken to harvest each crop per gram or kg whichever is appropriate.

Just a quick proviso on polyculture from my understanding and reading (not my experience, because I can't claim to have it).

The overall crop yield per square meter should be higher, but for an individual crop will be lower. For example you plant carrots and cabbage together (maybe? i dunno if that example works) and the carrots are smaller and cabbage is lighter, but per square meter of crop space you would supposedly get a higher total yield (combined weights of carrots and cabbage) than if you did the same crops in a separate row/bed for each.

If my understanding is correct that is an important consideration when comparing yields.

Interesting experiment!  I'd consider the classic Three Sisters planting, although I don't think corn is on your list.  Roughwood  (www.seedways.org) has both a northern and a southern Three Sisters package as well as a Five Sisters.  You could get two of the same set and plant one combined and the other separated, trying to keep the beds the same in all other conditions.  

I would have to look at yield as a % of the bed each plant took up, or as an average over all the plants if I can't workout which plant had which bit of space.
Three sisters wouldn't work as the only thing I grow is the winter squash and I don't grow that in the bed system as it takes way more space. We don't have the climate for maize or dried beans, some years we can get a crop and others we can't.

There's also the issue of what is a pollyculture. the picture on wikipedia

Does not fit my idea of one. I grow like this picture with rather larger paths as I have big clumsy feet and want to get a wheelbarrow in without squashing everything. Many of the pictures you find when you search for pollyculture vegetables are rows of veg then a path then a row of a different vegetable, and that is what I do anyway, simply because I do not grow an entire field of one vegetable.

I'm thinking something more like this.

I don't think yields will necessarily even drop for a given plant in a well done polyculture.  For example, I've seen folks growing dill plants throughout their cucumber hill plantings and the dill casts almost no shade, while potentially providing some benefits (not sure on that).  I can't imagine that the dill reduces the yield of the cukes.

Another thing to consider is to grow plants together and selectively breed them together in polycultures.  I've read articles where selections carried out this way perform much better as selection is carried out with plants that perform best under these polyculture conditions.  To me this represents a great opportunity to greatly improve crop output.

Cris Reed wrote:Interesting experiment!  I'd consider the classic Three Sisters planting, although I don't think corn is on your list.  Roughwood  (www.seedways.org) has both a northern and a southern Three Sisters package as well as a Five Sisters.  You could get two of the same set and plant one combined and the other separated, trying to keep the beds the same in all other conditions.  

Thank you - I’ve been reading about three sisters and really like the Description of the northern collection

In my experience, experimenting is a great way to learn what works, and doesn’t work, in your own situation. I am a big experimenter. I’ve found that polyculture works great for me in some aspects, not so great in others. It all depends what sort of polyculture are trying to incorporate, and by what method you do it.

I have also learned that what works on my one farm, doesn’t necessarily work well on the other farm 5 miles away. I am now farming a piece of land 12 miles away and it requires many very different methods in order to be productive and successful with that land’s characteristics.

So I would suggest you try things and figure out what works for you. Permaculture and polyculture ideas need to be tailored to the situation. But sometimes non-polyculture will produce more food in a sustainable fashion……it just uses different ideas.

To me a  poly culture system without a nitrogen fixing plant, just isn't right.
But I know that for other a polyculture system can be made up of just:
Brassica oleracea Acephala group – kale
Brassica oleracea Viridis group – collard greens
Brassica oleracea Alboglabra group – kai-lan (Chinese broccoli)
Brassica oleracea Botrytis group – cauliflower, Romanesco broccoli, and broccoflower
Brassica oleracea Capitata group – cabbage
Brassica oleracea Gemmifera group – Brussels sprouts
Brassica oleracea Gongylodes group – kohlrabi
Brassica oleracea Italica group – broccoli

One of the biggest benefits I get out of polyculture is less pest damage, thus ultimately more harvestable food. While one row of beets might get devastated by flea beetle, other rows are completely clear of the pest. By staggering the crops around and interplanting other crops, the pests seem to leave some alone while only attacking select others.

Short answer (looking specifically at diversity in grasslands):



Long answer (including a look at crop plants):



And if you really want to geek out, I highly recommend the other three videos in that series.

Sounds like you are describing the polyculture veggie garden that Gaia’s garden outlined. The timing and varieties might not be the same for you, but I think some general principles will be similar. As far as I recall, they were:1) broadcast the seeds over the space, with different size seeds broadcast separately so the big seed doesn’t all fall closer in. 2) don’t plant each crop at its monoculture density - plant more widely to leave space for other plants. The exact spacing will probably take some experimentation to optimize for your mix. 3) be sure to thin/ harvest fast growing plants so the later ones can fill the space. I am often too timid/busy with the early thinning and harvesting, and the next thing I know my lettuce is bolting and crowding out the chard.
I have tried this technique, and found that the advantage is often in the early growth - an early heat wave can dry out a bed of slow germinating seeds, but if they are shaded by the rapidly growing arugula, the germination will improve. The disadvantage is that it is harder to harvest, as things become easy to miss in the veggie jungle.
Good luck, let us know what you find

As an addendum to my previous post, Lina reminded me of a previous video I found.

I've been making a lot of observations over the past couple years as I've attempted to grow all of my own food. I've basically never grown in neat little rows of individual crops, but with the pandemic I decided it would be easier from an organizational standpoint to do so. And it's been hell (in no small part because of the atrocious weather we've had the past couple of years). I haven't been able to get all of my planting done and I've been wasting all of my time on planting at the expense of the things I'd already planted previously. This way of doing things just wasn't working for me.

And then I thought back to the best garden I've grown, in a mere 100 sq. ft., back when I still lived in town. It was a jumbled up mess. It was a mix of sweet corn, cilantro, zucchini, kale, pole beans, and lettuce that I literally had to wade through to get to anything. I ended up picking 80 pounds of zucchini before I got sick of it and stopped eating it. A couple dozen ears of corn. As many green beans as I could tolerate and then another pound or more of dry beans on top of that. Plus a whole mess of greens and herbs. Again, in only 100 sq. ft.

Even before I found Dr. Jones's presentations, I'd been thinking a lot about how well that garden did. And I've been thinking about how the volunteers that came up this year and grew in conjunction with other crops did way better than anything I planted on purpose. And I've been absorbing Joseph's work on landraces and how saving seeds is important to adapt them not only to the local climate, but also to the methods used by the gardener. Of special note is how Joseph has selected for plants that grow quickly and can overtake the weeds. And from my visit to Paul Gautschi's Back To Eden garden, how he's selected for root crops (and improved his soil) such that they push each other out of the way rather than simply refusing to size up when they're overcrowded.

I don't think it's as simple as just grabbing some seeds off of a seed rack, throwing them on the ground, and saying that polycultures do or don't work. If you're planting seeds that were grown in a monoculture, they were selected for thriving in a monoculture, and then won't necessarily thrive in a polyculture. I think the research is clear that they'll produce more biomass, but the question from a food production standpoint is whether they'll produce more edible biomass. And I don't think that's something that will necessarily happen overnight. I think you have to save seeds from the plants that do best in a polyculture and select for those traits specifically over 2 or 3 generations.

My solution to wasting all my time on planting was to go Fukuoka style and mix up all of my seeds into seed balls and broadcast them over the garden and let them sort themselves out. If they die, great. I don't want them passing on their genetics. I've set up narrow paths two arm lengths apart so that I can always reach all of the plants, solving the access issue I had in my 100 sq. ft.  garden (I've often seen 4 ft. given as a width for double reach beds, but I can never comfortably reach the center, which would be further compounded by the wild mix of stuff that I'm growing, so using my actual arm length is important.) For management, weeding, harvesting, and selection are all the same thing. I might harvest all of the carrots between two paths, or from the half of the bed I can reach from a path. The best carrots get replanted for seed, the second best carrots get eaten, and anything that's too small or forked or whatever to deal with go to the livestock or are dropped as mulch. I don't want those things that can't hack it in this system to pass on their genes. And as I clear a spot, I put down seeds for the next crops to keep the ground covered.

That selection is important, though. As we speak, I have root crops in the ground that are massively outperforming their neighbors. Those are the ones that thrive in this system, and those are the ones whose offspring will thrive in this system. If I bought in new seeds each year, I'd continue to have a few plants that really excel, but most that just do okay or poorly. If I want to increase edible biomass in this system, then I have to save my own seeds. There's just no getting around it.

Which brings me back to the video I mentioned. I was trying to find examples of somebody who was successfully growing vegetable crops by just broadcasting a wide mix of seeds. I found one. This guy right here:

I've enjoyed reading the different opinions on this question, but personally it has created more questions that I would want to ask.

First, would be, what constitutes "polyculture"? Most people I have talked to, would describe that as multiple kinds of plants growing in one place. Most of those same people would say that "nature" is a polyculture. The question then is, how big is that one place things are growing in? There are places in the woods of Maine where there is a stand of pine trees with no other kinds of trees in that area. That area could be a couple acres. Is this still polyculture since it is natural? In my lawn there is a 2ft x 2ft area where I see only clover growing. Does this mean that spot is "monoculture"?

My personal belief is that most gardens with different rows containing different plants would be considered a polyculture. I have several 20ft x 30ft garden plots. I have 7 rows in each, and if each row has a different type of plant, I would still consider that a polyculture. Some would not. I still often do put multiple types of plants in the same row, but that brings me to my next question to consider.

Why are you doing polyculture? Is it simply because "polyculture" is good and "monoculture" is bad? I think most people who practice polyculture, do so for a reason. Many gardeners plant multiple types in one row in order to better use the space. One may be fast growing and be harvested about the time the other needs more space. Perhaps it is to help deter or confuse pests by planting strong smelling or attractive plants amongst the plants we want to harvest. Perhaps a plant with larger leaves can block weeds from a smaller or more slender plants. And there is certainly the diversity of the soil biology... which is its own lifetime of study.

Polyculture is not perfect depending on what you are trying to do. It can make things more complicated. It can make harvesting more difficult and less effcient. It can reduce yield per type (as has been mentioned). And, while some would call this sacrilege, I say that there are times to plant in "monoculture". If your garden is doing great with single plant types in each row... there is nothing wrong with that.

My belief on polyculture is much the same as my belief about technology. It's great when used properly. But I would never suggest someone use it simply because someone said to, or because it's "new", or because you want to be able to say that you use it. I like the saying "You don't need a drill bit, you need a hole". I believe polyculture should be used to solve a problem, but make sure to identify the problem and use the right tool. Don't grab a tool and then look for what to do with it.

Matt McSpadden wrote:I've enjoyed reading the different opinions on this question, but personally it has created more questions that I would want to ask.

I can promise you that no forest you see on the east coast especially, and almost anywhere else in the world that isn't too remote for people to get to, is natural. It's all been cut down repeatedly for timber and to make room for European agriculture. The reason you see monocultures of pine is because that's the most valued as cheap lumber. Hardwoods are certainly harvested and used for lumber when they appear as "weeds" in a timber stand, and are quite valuable. The oaks that were taken off of the land here when the owner had it clear cut sold for $50,000 apiece, and a truck with 3 logs on it required it's own security detail because it was worth so much. But did the foresters replant any of these high value trees? No. Because they're too messy to manage, too slow growing, and not guaranteed to grow into a useable shape. Doug fir grows tall, fast, and straight, so they replant a monoculture of that. Other species are weeds that they're only happy about if they happen to find them at a useable size when they give to harvest the conifers. Anything that isn't a issue l useable size or shape is cut down and burned to "get it out of that way."

But this experiment in monocultural timber is failing. Japan's monocultural conifers are dying. Scandinavia's monocultural conifers are dying. Even here, disease is starting to spread amongst the Doug firs because there's nothing to stop it. And recent research has discovered that these monocultural timber stands transpire so much water in the 20 years before they're harvested that they're actively draining the groundwater that literally everything depends on to live.

But even before the insanity of European land management hit these shores, hardly any of the forests were natural. Modeled on natural ecosystems, sure, but they were heavily managed by the nations that existed here for food and resource production. Desirable species were encouraged and protected, and undesirable species were discouraged.

So to point at any forest in the U.S., with the possible exception of the remotest parts of the Olympic peninsula, as an example of what's natural is objective lunacy.

And to understand the role of soil microbiology hardly takes a lifetime. We have great educators that are passionate about the field who can teach you a fairly comprehensive fundamentals course in about an hour. In 8 to 12 hours you can absorb most of what there is to know as a non-researcher.

Case in point, yes, your clover is in a polyculture if it's only 2 feet across... unless you've sprayed herbicide on everything beyond that 2 feet. The confirmed benefits of polyculture stem from the ability of the plants to exchange nutrients and rhizospheric/endophytic microbes with dissimilar plants. Barring an allelopathic response, the benefit is derived from the plants roots touching, or being close enough to be bridged by mycelial networks. Most of the disease resistance, pest resistance, drought resistance we observe in plants we now know has little to do with the plant itself and more to do with the microbes it associates with. Each kind of plant produces different exudates which feed different populations of bacteria, and the combinations of exudates from different types of plants feed a more diverse set of microbes that either could on it's own (and creates soil at a greater depth than a monoculture, as shown in the Jena experiment.)

One of the best examples we have of how this works is with drought resistance. A root crop might associate with a particular bacterium that an herb doesn't, but if the herb is growing in close proximity to that root crop, it can release a chemical signal to recruit that bacterium. In exchange for feeding and housing that bacterium, it induces physiological changes in the herb, including cell wall thickening, which happens to be a key strategy in preventing moisture loss in the face of drought.

And back to the subject of conifers, we now know that there's an important relationship between conifers and hardwoods. Hardwoods have vastly superior photosynthetic capacity... when they have leaves. So much photosynthetic capacity that they end up producing far more carbohydrates than they could ever use. So, in a healthy system, what do they do? They share some of that surplus with the lagging conifers to keep them growing healthy and strong. And what do they get out of it? In the fall and winter, when the hardwoods can't photosynthesize at all, the conifers return the favor.

If industrial farms operating over thousands of acres see a cost benefit to growing a polyculture, then management is hardly an issue at the home scale. It's just a question of what plants, layout, and management style works for the grower. It's still more common to see complex polycyltures being used as cover crops on a large scale, but simpler combinations of plants are finding value amongst large scale commercial food and ethanol producers. Those producers are growing soybeans in the row with their corn crop. They aren't harvesting those soybeans, or tilling them in for organic matter. They're growing them with their corn because just the presence of soybeans eliminates their need for nitrogen fertilizer at a significant cost savings.

I can promise you that no forest you see on the east coast especially, and almost anywhere else in the world that isn't too remote for people to get to, is natural. It's all been cut down repeatedly for timber and to make room for European agriculture.

If your definition of "natural" is "untouched by humans", then I absolutely agree with you on this first part. I think you are absolutely correct that anywhere on earth probably has already had people cutting down trees and changing things. I don't know that it has all been for "European agriculture", some was simply for boat building or other structures, but certainly there has been disturbance.

The reason you see monocultures of pine is because that's the most valued as cheap lumber.

I would have to disagree with this statement. It was not that long ago that Maine was clearcut for agriculture. I believe in the early 1900's, though that is a guess, nearly all the trees were cut down. Since then, there are many parts of the state that were allowed to grow back without any sort of intervention for 70-100 years or more. These pockets I'm talking about were not planted on purpose for lumber, but that particular spot happened to have lots of pine tree seeds, or was particularly conducive to growing pine trees. While most of the forest is quite diverse, you get clumps of certain kinds of trees, which I argue is perfectly "natural".

And to understand the role of soil microbiology hardly takes a lifetime.

You are correct that understanding the role of soil microbiology does not take a lifetime. But I was speaking of soil biology itself. For a comparison, there are people who have dedicated 30 years of their life to studying one type of animal and still learn new things in the later years. A mere teaspoon of healthy soil can contain hundreds of millions of bacteria, 10s of thousands of different types of life. There are millions if not billions of combinations of plants, roots, bacteria, and whatnot. I remember hearing there are trillions of transactions that happen in the soil between fungus and bacteria and plants and various animals of different sizes (I do no recall the area and timeframe). If anything, I would argue that a lifetime of study is an understatement.

I can see that we need a definite objective. There's thousands of ways to plant a polyculture and lots of definitions of best. So I think you'll have to figure out a lot of what works best for you rather than figuring out what a permaculturally purist polyculture would be. I'm not a purist. I'm not even sure that permaculture can be a purist.

My thoughts are that you're probably going to have to experiment for a few years to figure it out. I just planned out a garden at our new house, and even with some previous experience I can see that it's going to be a few years before I figure out where everything fits in. So you might have to experiment with different kinds/varieties of plants.

The goals as I can see them are:
Increased productivity (This would be overall output rather than measuring just carrots per square foot compared to carrot-only beds)
Decreased maintenance/work. Less watering, fertilizing, weeding, etc.
Increased pest/disease resistance.

Unless you keep meticulous notes on every detail including lots that probably don't seem important yet you're probably going to have trouble with anything more than a subjective "I think this was better/worse than..."
Abnormal weather and pest pressure are the norm so this is part of why you'd need more than one year.

A resource I would start with is the book "Carrots Love Tomatoes." It's about plants that do well together. One experiment option option is to find 2-3 kinds of plants the book says do well together and mix them together in your test plot.

Another experiment option is to scatter a few seeds of everything you grow on your test bed and see what does well. Then in future years plant those together.

Another option lots of us on permies do is to find something we don't already have and plant it just because. Like I noticed you didn't mention having  raspberries or really much in the way of perennials. I like raspberries so I would plant those. Actually I think that anyone interested in permaculture will tend to gravitate toward perennials since they don't require yearly tilling to keep your ground in a perpetual state of disturbance. Annuals tend to be wound management/scabbing in function and ecosystems tend toward something better developed.

Another option is to grow something like clover in your off season as a green manure. Or you could find something like that to grow in between your other plants. Maybe on the path way. Personally I'm not sure I'd grow clover or whatever in a vegetable garden. At least at my scale of gardening I view a garden as an intensive system with external inputs of fertility. I'm in the city where I have access to wood chips and vegetable scraps but minimal space in which to grow my own fertility. (I'm sure lots of people will disagree with that statement.) I'm sure it's possible with more planning or effort. At the moment I view this as the ecosystem of the city, where I'm using wastes available here to try to get the biggest dollar value in food for me.

You could research plants that help you control pests. This could be planting something like yarrow that attracts predatory insects or it could be planting a bait specie whose purpose is to distract your bugs from the plants you care about.

You could find a perennial fruit/bush guild and experiment with that. It already worked well for someone. Obviously this is a longer time commitment.

Given where you are, I think I'd steer you more toward the first option using foods you already grow, just experimenting with growing them together. Then I'd also work on planting non-food plants that will help you with your pest problems as well as leaving some weed plants around. You might discover that some of them also help with your pests.

Daniel

I think it would definitely depend on your climate and issues. I love interplanting corn with members of the cucurbit family because our summers are so hot and dry that they really benefit from the shade of the corn. And the soil is kept cooler and needs less water because of the shade from the cucurbits. Can I plant the corn as close, no, but I don't need a separate bed for the melons or squash. But none of these things are an issue in your climate.

I also like to plant short season plants like radishes while waiting for long season plants to fill a space, like tomatoes or peppers.

   

Skandi Rogers wrote:Many of the pictures you find when you search for pollyculture vegetables are rows of veg then a path then a row of a different vegetable,
    I'm thinking something more like this.

WOW! Whoee! IF I could grow onions and carrots like that I wouldn't worry about 'poly-culture' - I would be worrying about where and how much my canning jars were going to run me.

I wish, I wish, I wish I could grow those in my garden that large.

About 3 years ago I did let 3 Carrot stalks keep growing because they were already about 4 ft. tall as I had ignored that raised bed in  the cleanup sweep. Two grew to be over 8 ft tall. I couldn't believe it when I pulled those out so I laid two 2" X 4" X 8 ft studs out and placed the carrots alongside those just to prove to people that they really were that tall.

I'd still just as soon as have my veggies growing like yours.